<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP 4.3.2 or newer
 *
 * @package		CodeIgniter
 * @author		ExpressionEngine Dev Team
 * @copyright	Copyright (c) 2006 - 2009, EllisLab, Inc.
 * @license		http://codeigniter.com/user_guide/license.html
 * @link		http://codeigniter.com
 * @since		Version 1.0
 * @filesource
 */

// ------------------------------------------------------------------------

/**
 * Shopping Cart Class
 *
 * @package		CodeIgniter
 * @subpackage	Libraries
 * @category	Shopping Cart
 * @author		ExpressionEngine Dev Team
 * @link		http://codeigniter.com/user_guide/libraries/cart.html
 */
class CI_Cart {

// These are the regular expression rules that we use to validate the product ID and product name
  var $product_id_rules	= '\.a-z0-9_-'; // alpha-numeric, dashes, underscores, or periods
  var $product_name_rules	= '\.\:\-_ a-z0-9'; // alpha-numeric, dashes, underscores, colons or periods

  // Private variables.  Do not change!
  var $CI;
  var $_cart_contents	= array();


  /**
   * Shopping Class Constructor
   *
   * The constructor loads the Session class, used to store the shopping cart contents.
   */
  function CI_Cart($params = array()) {
  // Set the super object to a local variable for use later
    $this->CI =& get_instance();

    // Are any config settings being passed manually?  If so, set them
    $config = array();
    if (count($params) > 0) {
      foreach ($params as $key => $val) {
        $config[$key] = $val;
      }
    }

    // Load the Sessions class
    $this->CI->load->library('session', $config);

    // Grab the shopping cart array from the session table, if it exists
    if ($this->CI->session->userdata('cart_contents') !== FALSE) {
      $this->_cart_contents = $this->CI->session->userdata('cart_contents');
    }
    else {
    // No cart exists so we'll set some base values
      $this->_cart_contents['cart_total'] = 0;
      $this->_cart_contents['total_items'] = 0;
    }

    log_message('debug', "Cart Class Initialized");
  }

  // --------------------------------------------------------------------

  /**
   * Insert items into the cart and save it to the session table
   *
   * @access	public
   * @param	array
   * @return	bool
   */
  function insert($items = array()) {
  // Was any cart data passed? No? Bah...
    if ( ! is_array($items) OR count($items) == 0) {
      log_message('error', 'The insert method must be passed an array containing data.');
      return FALSE;
    }

    // You can either insert a single product using a one-dimensional array,
    // or multiple products using a multi-dimensional one. The way we
    // determine the array type is by looking for a required array key named "id"
    // at the top level. If it's not found, we will assume it's a multi-dimensional array.

    $save_cart = FALSE;
    if (isset($items['id'])) {
      if ($this->_insert($items) == TRUE) {
        $save_cart = TRUE;
      }
    }
    else {
      foreach ($items as $val) {
        if (is_array($val) AND isset($val['id'])) {
          if ($this->_insert($val) == TRUE) {
            $save_cart = TRUE;
          }
        }
      }
    }

    // Save the cart data if the insert was successful
    if ($save_cart == TRUE) {
      $this->_save_cart();
      return TRUE;
    }

    return FALSE;
  }

  // --------------------------------------------------------------------

  /**
   * Insert
   *
   * @access	private
   * @param	array
   * @return	bool
   */
  function _insert($items = array()) {
  // Was any cart data passed? No? Bah...
    if ( ! is_array($items) OR count($items) == 0) {
      log_message('error', 'The insert method must be passed an array containing data.');
      return FALSE;
    }

    // --------------------------------------------------------------------

    // Does the $items array contain an id, quantity, price, and name?  These are required
    if ( ! isset($items['id']) OR ! isset($items['qty']) OR ! isset($items['price']) OR ! isset($items['name'])) {
      log_message('error', 'The cart array must contain a product ID, quantity, price, and name.');
      return FALSE;
    }

    // --------------------------------------------------------------------

    // Prep the quantity. It can only be a number.  Duh...
    $items['qty'] = trim(preg_replace('/([^0-9])/i', '', $items['qty']));
    // Trim any leading zeros
    $items['qty'] = trim(preg_replace('/(^[0]+)/i', '', $items['qty']));

    // If the quantity is zero or blank there's nothing for us to do
    if ( ! is_numeric($items['qty']) OR $items['qty'] == 0) {
      return FALSE;
    }

    // --------------------------------------------------------------------

    // Validate the product ID. It can only be alpha-numeric, dashes, underscores or periods
    // Not totally sure we should impose this rule, but it seems prudent to standardize IDs.
    // Note: These can be user-specified by setting the $this->product_id_rules variable.
    if ( ! preg_match("/^[".$this->product_id_rules."]+$/i", $items['id'])) {
      log_message('error', 'Invalid product ID.  The product ID can only contain alpha-numeric characters, dashes, and underscores');
      return FALSE;
    }

    // --------------------------------------------------------------------

    // Validate the product name. It can only be alpha-numeric, dashes, underscores, colons or periods.
    // Note: These can be user-specified by setting the $this->product_name_rules variable.
    if ( ! preg_match("/^[".$this->product_name_rules."]+$/i", $items['name'])) {
      log_message('error', 'An invalid name was submitted as the product name: '.$items['name'].' The name can only contain alpha-numeric characters, dashes, underscores, colons, and spaces');
      return FALSE;
    }

    // --------------------------------------------------------------------

    // Prep the price.  Remove anything that isn't a number or decimal point.
    $items['price'] = trim(preg_replace('/([^0-9\.])/i', '', $items['price']));
    // Trim any leading zeros
    $items['price'] = trim(preg_replace('/(^[0]+)/i', '', $items['price']));

    // Is the price a valid number?
    if ( ! is_numeric($items['price'])) {
      log_message('error', 'An invalid price was submitted for product ID: '.$items['id']);
      return FALSE;
    }

    // --------------------------------------------------------------------

    // We now need to create a unique identifier for the item being inserted into the cart.
    // Every time something is added to the cart it is stored in the master cart array.
    // Each row in the cart array, however, must have a unique index that identifies not only
    // a particular product, but makes it possible to store identical products with different options.
    // For example, what if someone buys two identical t-shirts (same product ID), but in
    // different sizes?  The product ID (and other attributes, like the name) will be identical for
    // both sizes because it's the same shirt. The only difference will be the size.
    // Internally, we need to treat identical submissions, but with different options, as a unique product.
    // Our solution is to convert the options array to a string and MD5 it along with the product ID.
    // This becomes the unique "row ID"
    if (isset($items['options']) AND count($items['options']) > 0) {
      $rowid = md5($items['id'].implode('', $items['options']));
    }
    else {
    // No options were submitted so we simply MD5 the product ID.
    // Technically, we don't need to MD5 the ID in this case, but it makes
    // sense to standardize the format of array indexes for both conditions
      $rowid = md5($items['id']);
    }

    // --------------------------------------------------------------------

    // Now that we have our unique "row ID", we'll add our cart items to the master array

    // let's unset this first, just to make sure our index contains only the data from this submission
    unset($this->_cart_contents[$rowid]);

    // Create a new index with our new row ID
    $this->_cart_contents[$rowid]['rowid'] = $rowid;

    // And add the new items to the cart array
    foreach ($items as $key => $val) {
      $this->_cart_contents[$rowid][$key] = $val;
    }

    // Woot!
    return TRUE;
  }

  // --------------------------------------------------------------------

  /**
   * Update the cart
   *
   * This function permits the quantity of a given item to be changed.
   * Typically it is called from the "view cart" page if a user makes
   * changes to the quantity before checkout. That array must contain the
   * product ID and quantity for each item.
   *
   * @access	public
   * @param	array
   * @param	string
   * @return	bool
   */
  function update($items = array()) {
  // Was any cart data passed?
    if ( ! is_array($items) OR count($items) == 0) {
      return FALSE;
    }

    // You can either update a single product using a one-dimensional array,
    // or multiple products using a multi-dimensional one.  The way we
    // determine the array type is by looking for a required array key named "id".
    // If it's not found we assume it's a multi-dimensional array
    $save_cart = FALSE;
    if (isset($items['rowid']) AND isset($items['qty'])) {
      if ($this->_update($items) == TRUE) {
        $save_cart = TRUE;
      }
    }
    else {
      foreach ($items as $val) {
        if (is_array($val) AND isset($val['rowid']) AND isset($val['qty'])) {
          if ($this->_update($val) == TRUE) {
            $save_cart = TRUE;
          }
        }
      }
    }

    // Save the cart data if the insert was successful
    if ($save_cart == TRUE) {
      $this->_save_cart();
      return TRUE;
    }

    return FALSE;
  }

  // --------------------------------------------------------------------

  /**
   * Update the cart
   *
   * This function permits the quantity of a given item to be changed.
   * Typically it is called from the "view cart" page if a user makes
   * changes to the quantity before checkout. That array must contain the
   * product ID and quantity for each item.
   *
   * @access	private
   * @param	array
   * @return	bool
   */
  function _update($items = array()) {
  // Without these array indexes there is nothing we can do
    if ( ! isset($items['qty']) OR ! isset($items['rowid']) OR ! isset($this->_cart_contents[$items['rowid']])) {
      return FALSE;
    }

    // Prep the quantity
    $items['qty'] = preg_replace('/([^0-9])/i', '', $items['qty']);

    // Is the quantity a number?
    if ( ! is_numeric($items['qty'])) {
      return FALSE;
    }

    // Is the new quantity different than what is already saved in the cart?
    // If it's the same there's nothing to do
    if ($this->_cart_contents[$items['rowid']]['qty'] == $items['qty']) {
      return FALSE;
    }

    // Is the quantity zero?  If so we will remove the item from the cart.
    // If the quantity is greater than zero we are updating
    if ($items['qty'] == 0) {
      unset($this->_cart_contents[$items['rowid']]);
    }
    else {
      $this->_cart_contents[$items['rowid']]['qty'] = $items['qty'];
    }

    return TRUE;
  }

  // --------------------------------------------------------------------

  /**
   * Save the cart array to the session DB
   *
   * @access	private
   * @return	bool
   */
  function _save_cart() {
  // Unset these so our total can be calculated correctly below
    unset($this->_cart_contents['total_items']);
    unset($this->_cart_contents['cart_total']);

    // Lets add up the individual prices and set the cart sub-total
    $total = 0;
    foreach ($this->_cart_contents as $key => $val) {
    // We make sure the array contains the proper indexes
      if ( ! is_array($val) OR ! isset($val['price']) OR ! isset($val['qty'])) {
        continue;
      }

      $total += ($val['price'] * $val['qty']);

      // Set the subtotal
      $this->_cart_contents[$key]['subtotal'] = ($this->_cart_contents[$key]['price'] * $this->_cart_contents[$key]['qty']);
    }

    // Set the cart total and total items.
    $this->_cart_contents['total_items'] = count($this->_cart_contents);
    $this->_cart_contents['cart_total'] = $total;

    // Is our cart empty?  If so we delete it from the session
    if (count($this->_cart_contents) <= 2) {
      $this->CI->session->unset_userdata('cart_contents');

      // Nothing more to do... coffee time!
      return FALSE;
    }

    // If we made it this far it means that our cart has data.
    // Let's pass it to the Session class so it can be stored
    $this->CI->session->set_userdata(array('cart_contents' => $this->_cart_contents));

    // Woot!
    return TRUE;
  }

  // --------------------------------------------------------------------

  /**
   * Cart Total
   *
   * @access	public
   * @return	integer
   */
  function total() {
    return $this->_cart_contents['cart_total'];
  }

  // --------------------------------------------------------------------

  /**
   * Total Items
   *
   * Returns the total item count
   *
   * @access	public
   * @return	integer
   */
  function total_items() {
    return $this->_cart_contents['total_items'];
  }

  // --------------------------------------------------------------------

  /**
   * Cart Contents
   *
   * Returns the entire cart array
   *
   * @access	public
   * @return	array
   */
  function contents() {
    $cart = $this->_cart_contents;

    // Remove these so they don't create a problem when showing the cart table
    unset($cart['total_items']);
    unset($cart['cart_total']);

    return $cart;
  }

  // --------------------------------------------------------------------

  /**
   * Has options
   *
   * Returns TRUE if the rowid passed to this function correlates to an item
   * that has options associated with it.
   *
   * @access	public
   * @return	array
   */
  function has_options($rowid = '') {
    if ( ! isset($this->_cart_contents[$rowid]['options']) OR count($this->_cart_contents[$rowid]['options']) === 0) {
      return FALSE;
    }

    return TRUE;
  }

  // --------------------------------------------------------------------

  /**
   * Product options
   *
   * Returns the an array of options, for a particular product row ID
   *
   * @access	public
   * @return	array
   */
  function product_options($rowid = '') {
    if ( ! isset($this->_cart_contents[$rowid]['options'])) {
      return array();
    }

    return $this->_cart_contents[$rowid]['options'];
  }

  // --------------------------------------------------------------------

  /**
   * Format Number
   *
   * Returns the supplied number with commas and a decimal point.
   *
   * @access	public
   * @return	integer
   */
  function format_number($n = '') {
    if ($n == '') {
      return '';
    }

    // Remove anything that isn't a number or decimal point.
    $n = trim(preg_replace('/([^0-9\.])/i', '', $n));

    return number_format($n, 2, '.', ',');
  }

  // --------------------------------------------------------------------

  /**
   * Destroy the cart
   *
   * Empties the cart and kills the session
   *
   * @access	public
   * @return	null
   */
  function destroy() {
    unset($this->_cart_contents);

    $this->_cart_contents['cart_total'] = 0;
    $this->_cart_contents['total_items'] = 0;

    $this->CI->session->unset_userdata('cart_contents');
  }


}
// END Cart Class

/* End of file Cart.php */
/* Location: ./system/libraries/Cart.php */